What is the law upon which Justice Street relied?

It appears that the law upon which Justice Street relied stems from the English case of Holroyd v. Marshall (1862), 10 H.L.C. 191, 11 E.R. 999. The first two paragraphs of the headnote of that case read as follows: In equity it is not necessary for the alienation of existing property that there should be a formal deed of conveyance. A contract to transfer the property, given for valuable consideration, provided it is capable of being the subject of decree for specific performance, passes it at once, and the vendor becomes a trustee for the vendee. This rule applies to personal property, as well as to real estate. Such a contract, if made with respect to the sale or mortgage of future acquired property, being capable of specific performance, transfers the beneficial interest in the property, as soon as it is acquired, to the vendee or mortgagee, who may have an injunction to restrain its removal.